Issue 586183  describes a bug where image elements allocated via "new Image()" and not part of the document's hierarchy are being GC'd before their onload handlers are called.

This problem has surfaced a couple of times before in Chrome, and there aren't enough stress tests which can catch it. It has manifested itself as random failures of image- and texture-related WebGL conformance tests in the past.

A stress test is needed which will catch the bug more reliably.  Issue 604844  contains a JSFiddle that with appropriate modification seems to catch the bug about 50% of the time.